Many different types of wireless communication systems include base stations or access points in wireless local area networks (WLANs). The base stations or access points typically include components for wirelessly transmitting and receiving information. The base stations or access points typically interact with wireless devices (such as mobile telephones and computing devices) to provide wireless services (such as wireless voice and data services) to the wireless devices. Often times, the base stations or access points “overlap,” which means that multiple base stations or access points have overlapping coverage areas and can provide service to the same physical area. In this document, the phrase “base station” and its derivatives may be used to collectively refer to base stations, access points, and other similar structures.
Communication systems routinely engage in various sensing activities to identify sources of interference that can interrupt or degrade wireless communications. For example, in a wireless regional area network (WRAN), base stations often need to engage in “incumbent user” sensing. In these or other types of networks, the base stations may represent transmitters having a lower priority or right to use a particular wireless frequency or frequency channel. Other devices called “incumbent users” typically represent transmitters having a higher priority or right to use a particular wireless frequency or frequency channel. As a specific example, a television broadcaster may represent an incumbent user having a higher priority to use a particular wireless frequency or frequency channel.
The base stations in these or other types of networks often need to sense whether they are or could be interfering with an incumbent user. This may involve simply detecting the presence of an incumbent user that could experience interference due to the operation of one or more of the base stations. If an incumbent user having a higher priority to a frequency or frequency channel is detected, a base station could take suitable corrective action. For instance, the base station could change the wireless frequency or frequency channel it uses to communicate with wireless devices in the network. Also, the base stations may engage in incumbent user sensing to determine if a particular wireless frequency or frequency channel is currently available for use by the base stations (i.e. no incumbent users are detected on a particular wireless frequency or frequency channel).